maxima: 5.87 p (very strong), 8.80 p (very strong) and 9.05 method of Ladenburg and S ~ h o l t zin~ 207, ~ yield. A con(very strong). densation between 4.7 g. (0.027 mole) of I X and 3.7 ml. Anal. Calcd. for C10H2002: C, 69.72; 13, 11.70. Found: (3.0 g., 0.030 mole) of pinacolone in 20 ml. of absolute ethanol was catalyzed by a sodium ethoxide solution preC, 69.66; H, 10.94. The 2,4-dinitrophenylhydrazone gave yellow needles pared from 1 g. of sodium and 10 ml. of absolute ethanol as before. After 24 hours 150 ml. of water was added and the from ethanol, m.p. 90-91". crystalline precipitate was recrystallized from ethanol Anal. Calcd. for C16Hz40bi*rT4: C, 54.53; H , 6.87. giving 4,4-dimethyl-l-(3,4-methylenedioxyphenyl)1-penFound: C. 54.28; €1, 7.03. ten-3-one (X), m.p. 93-94', yield 4.5 g. (7370). Pace'6 Several attempts to condense pivalaldehyde with I11 in reported m.p. 98' for X prepared from a piperonal-pinacotetrahydrofuran by the method employed above failed, lone condensation. The ultraviolet absorption spectrum3' yielding only starting materials. of X in ethanol showed a shoulder at 221 mp (7900) and a t Condensation of Benzaldehyde with 2,2-Dimethyl-4211 mg (9000) and emax 9500, hma, 250 m p and emax 18,000, hexen-3 one.--A solution of 1.0 g. (0.010 mole) of benzalAmex 339 mg. dehyde and 1.2 g. (0.0095 mole) of I11 in 10 ml. of absolute Anal. Calcd. for Cl&Il&: C, 72.36; H , 6.94. Found: ethanol was cooled to 0" and treated with a cooled sodium ethoxide solution prepared from 0.3 g. of sodium and 10 c , 71.68; rs, 7.05. ml. of absolute ethanol and allowed to stand overnight. The 2,4-dinitrophenylhydrazone gave two varietie4 of \Vater was added and the mixture was extracted with ether. crystals from ethanol-ethyl acetate: fine yellow needles The ethereal extracts were dried over anhydrous magnesium which became orange-red a t 120' and melte? a t 148-155"; qulfate, concentrated and distilled giving 2,2-dimethgl-7and thick shiny red needles, m.p. 148-153 , mixed m.p. phenpl-4,6-heptadien-3-one(\'II), b.p. 140-142" (1 mm.), of the two forms, 148-155'. Recrystallized from m e t F n o l yield 0.58 g. (28%). the yellow needles gave orange plates, m.p. 149.5-156 The 2,4-dinitrophenylhydrazone was recrystallized from A n d . Calcd. for C20H2006N4: C, 58.24; H, 4.89. ethanol-ethyl acetate, m.p. 202-204'. Found: C, 57.94; H , 5.13. iluthentic VI1 was prepared by a similar condensation between 11.9 ml. (13.2 g., 0.10 mole) of cinnamaldehyde and The red needles were recrystallized from ethanol. m.p. 12.3 ml. (9.8 g., 0,098 mole) of pinacolone in 45 ml. of ab149-156". zolute ethanol using a sodium ethoxide solution prepared Anal. Calcd. for C?o152,306N4: c , 58.21; €1, 4.89. from 2.5 g of sodium and 30 ml. of absolute ethanol. The product, b.p. 137-141" (1.5 mm.), yield 8.0 g. (38Yp),was Found: C, 57.9; H , 4.85. crystallized by chilling in an acetone-Dry Ice mixture. Both derivatives gave negative Knorr tests40 indicating .Ifter two recrystallizations from ethanol the yellow crystals that neither possessed a pyrazoline structure. Similar melted a t 56-57°.38 phenomena were observed by Goheen41in the preparation of Anal. Calcd. for CIBH180:C, 84.07; H , 8.47. Found: patulin phenylhydrazone. -4 condensation of piperonal (4.5 g., 0.030 mole) with C, 83.23; H, 8.66. The 2,4-dinitrophenylhydrazone gave red needles from pinacolone (3.0 g., 0.030 mole) carried out in the same ethanol, m.p. 203-204", mixed m.p. with derivatives ob- manner gave 6.6 g. (9595) of X, m.p. 92.5-93.5", mixed m.p. with previous material (1n.p. 93-94') 92.5-94'. tained previously (m.p. 202-204'), 202-204'. The 2,4-dinitrophenylhydrazoneof authentic X gave t+ ilnal. Calcd. for C21H2204N4: C, 63.94; H, 5.62. same yellow and red crystalline mixture, m.p. 148-156 , I mind: C, 63.S7; H, 5 73. mixed m.p. with previous material 149-156'. Condensation of 3-(3,4-Methylenedioxyphenyl)-2-pro(39) A Ladenburg and 31 Scholtz, Ber., 27, 2958 (1891). penal (IX) with Pinacolone.-IX was prepared by the p
.
( 3 8 ) 4,4-Dimelhyl-l-phenyl-l-penten-3-011e (colorless), t h e product of the condensation of benzaldehyde and pinacolone, is reported t o have m . p . 4 3 O . b.p. 144-145> (10 mm.) bv G. A. Hill, C. S. Spear and J S. Lachoivicz (THIS JUI;ILKAI., 45, 1259 (1973)).
[CONTRI~UTIO FROM N
THE
Vinyl Alcohols. B Y ~ ~ E Y N O LCD. F U S O N ,
(40) L. Knorr ibid.. 26, 100 (1893). (41) D. W. Goheen, Dissertation, University of Washington, 1951 p. 144.
SEATTLE, WASHINGTON
NOYESCHEYICAL LABORATORY, USIVERSITY OF ILLINOIS]
XX.I Reaction with Lead Tetraacetate
EVERETT W.
M A Y N E R T , TZI-LIEHT A N , ELhIER lvASSMUNDT3
R. TRUMBULL~ AND F. W.
RECEIVED DECEMBER 7, 1956 Five 2,2-diarylvinyl alcohols, when treated with lead tetraacetate, have been fouild to yield t h e acetates of the correspoudirig diarylglycolaldehydes.
A possible route to diarylacetaldehydes or to the corresponding vinyl alcohols is the cleavage of suitably constituted glycols with lead tetraacetate or with periodic acid. The latter reagent was used successfully to make mesitylphenylacetaldehyde (IT) from the glycol I.' Such a synthesis could not be effected, of course, if the product itself were attacked by the reagent. Experiment showed that lead tetraacetate con(1) For t h e preceding communication in this series see R. C . Fuson and T.-L. T a n , THISJOURNAL, 70, 002 (1948). (2) Rohm a n d Haas Research Assistant, 1945-1946; d u P o n t I'ellom, 1946--1947. (31 Standard Oil C!o of Indiana liellow, 1954-1955; Visking Corpcrati
